Key-positioning Vise Assembly For Automatic Key Cutter

Abstract

In a key-cutting machine of the type in which a cutter and stylus are moved relative to a key blank and a key, an improved vise assembly for automatically, accurately positioning the key and blank in a predetermined tracing and cutting disposition. The vise assembly includes a clamp head for picking up the key and blank in a partially aligned position responsive to tripping of a switch by insertion of a key and blank and thereafter advancing the same to a selected tracing and cutting position automatically, thus eliminating the likelihood that an improper cutting operation can be performed.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention is in the field of key-cutting machines, and more particularly key-cutting machines of the type in which a cutting wheel and a tracing stylus are movably mounted relative to a pair of spaced vises for holding a key blank and a key.

More particularly, this invention is in the field of cutting devices of the type described in which the various operations are, to a maximum extent, automatically performed.

2. The Prior Art

It is conventional to cut keys by providing a cutter wheel stylus on the one hand, and a pair of vises on the other hand. The vises may be charged with a key and key blank which are located in precise positions within the vises by pressing a portion of the key (normally the shoulder) against a reference or indexing portion of the vise.

A relative movement is then effected between the vises on the one hand and the cutter and tracer on the other, the movement being dictated by utilizing the engagement of the tracer against the pattern of the key to induce a concomitant movement between the cutter and the key blank, thus, in effect, milling the blank to conform to the pattern of the key.

In accordance with more recent adaptations of the above-described cutting machine concept, various phases of the key-cutting operation have been automatically carried out. For instance, it is known to provide mechanism for automatically relatively moving the vises in relation to the tracer and cutter.

In other machines the operation of developing clamping pressures for the key and key blank within the respective vises has been automatically carried out as a function of the operation of the device.

In still further developments, the insertion of the key and the key blank has been relied on to initiate the key-cutting cycle, including the clamping of the key and blank, the movement of the key and blank relative to the tracer and cutter, and the release of the key and blank at the completion of the cutting operation, to permit removal of the same from their respective vises.

It has been the consistent intention of designers of the various forms of key-cutting machines to arrive at an apparatus which is essentially foolproof, to the end that even persons totally inexperienced in the field of locksmithing and key cutting can, by following certain simple directions, produce a perfect replica or duplicate key.

Although a multiplicity of machines have been proposed to meet this end, no known cutter has heretofore been available by which completely satisfactory results can be consistently achieved. A principal difficulty in all cases has been the tendency or possibility that an inexperienced user might insert the key or key blank within its respective vise in such manner that the alignment between the blank and its vise differs from the alignment between the key and its vise. Obviously, when a cut is effected under such circumstances, the cuts in the key blank simply will not match the cuts in the pattern key. A mismatch of even a few thousandths of an inch in either depthwise or axial formation of the cuts will render the duplicate key unsuitable for operating the lock for which it was intended.

In an attempt to facilitate accurate positioning of keys, it has been proposed to use limit switches as locating expedients which trigger closing of the vise in response to insertion of a key. The theory behind such devices is that in the absence of tripping the switch, the vises cannot be actuated. Since the switch can presumably be tripped only with properly aligned keys, it was supposed that such systems would provide a foolproof key-cutting machine suitable for use, for instance, as a component of a coin-operated key-vending apparatus. Such devices have not proved to be practical since a significant percentage of miscut keys is still produced.

Without limitation, failure of these devices is attributed to the possibility of movement of the key after a switch has been triggered, due to the inherent variations in limit switches which permit a certain amount of overtravel after the switch is closed. There is also the possibility, in certain such machines, that the key may be skewed to a degree which will cause improper duplication yet nonetheless permit triggering of the switch.

SUMMARY OF THE INVENTION

The present invention relates to an automatic key cutter including a vise assembly, which vise assembly automatically shifts the key and key blank inserted into their respective vises from an initial, partly aligned position. The vise assemblies assure that the key and key blank will be oriented with extreme accuracy relative to their respective vises.

The vise assemblies include a movable clamp head which initially automatically grips the key and key blank at a partially aligned position responsive to insertion of a key and blank, and advances the same to a second, precisely aligned position. Preferably, the device includes secondary clamp means of more or less conventional nature, which firmly grip the key and blank in the second position and prevent shifting of the same in the course of cutting or tracing.

It is accordingly an object of the invention to provide in a key-cutting machine of the type described, automatic vise assemblies for the key and key blank which are effective to assure controlled positioning of said key and blank members.

It is a further object of the invention to provide an assembly of the type described which is foolproof and, hence, suitable for use as a component of a coin-operated vending machine or system whereby unskilled and unsupervised persons may effect the automatic duplication of a key.

It is a further object of the invention to provide a key-cutting machine of the type described which incorporates a key blank vise assembly and a key vise assembly which grasp a partially inserted key blank and key and advance the same from an initial to a second position relative to the vises.

To attain these objects and such further objects as may appear herein or be hereinafter pointed out, reference is made to the accompanying drawings, forming a part hereof, in which:

FIG. 1 is a plan view of a key-cutting apparatus in accordance with the invention, with certain conventional components of the key-cutting machine proper eliminated, and/or shown in dot and dash lines, more clearly illustrating the innovative portions of the apparatus;

FIG. 2 is a front elevational view of the apparatus of FIG. 1;

FIG. 3 is an enlarged perspective view of a vise assembly forming the principal subject matter of the present invention;

FIG. 4 is a magnified section taken on line 4--4 of FIG. 3;

FIG. 5 is a vertical section taken on line 5--5 of FIG. 3;

FIG. 6 is an exploded perspective view of the basic components of the vise assembly.

Turning now to the drawings, there is shown in FIG. 1 an essentially conventional key-cutting machine which has been adapted for automatic operation by incorporating therein a pair of key blank and key receiving and positioning vises 10, 10' , which constitute the principal advance hereof.

It should be understood from the outset that the vises may be employed in any of a series of different key-cutting machines, the specific cutting machine 11 illustrated herein being incorporated by way of example only and for purposes of complying with the requirements of the patent laws.

As more fully explained hereafter, the cutting machine is of the type in which the key and key blank vises are supported on a movable carriage, which carriage is shifted axially and pivotally relative to a fixedly positioned key-cutting wheel and stylus. It will, however, be appreciated that the vises are equally adapted for use in assemblies of the type in which the vises are stationary and the cutter and tracer are movable.

In accordance with the invention, 12 is a base or frame portion on which is pivotally mounted a carriage assembly 13. The carriage assembly is free to move axially inwardly and outwardly (up and down as viewed in FIG. 1) about the carriage support rod 14. The carriage may likewise be pivoted relative to the rod.

The frame 12 carries a motor (not shown) which may be fixed to a depending pivotal motor mount 15, the output drive pulley (not shown) of the motor being in driving connection with the input pulley 16, made fast to an input shaft 17 rotatably mounted in spaced bearings forming a part of the frame.

A conventional key cutter wheel 18 is carried on the shaft 17. A worm 19 meshes with drive gear 20, which gear, through a conventional secondary speed reduction gearing (not shown), slowly rotates the shaft 21, which is likewise journaled for rotation on the frame. The shaft 21 carries a box cam 22, having a continuous, outwardly open cam track 23 including axial components, it being understood that the cam track serves to drive the carriage forwardly and rearwardly for purposes of performing the cutting cycle and other operations hereinafter to be described.

24 is a heavy coil spring sleeved about the carriage support rod 14, the spring 24 serving to urge the carriage toward a forward position shown in FIG. 1. A follower pin 25, made fast to the carriage, extends into the track 23 of the box cam.

From the foregoing essentially conventional drive mechanism, it will be appreciated that rotation of the box cam will cause the carriage to be shifted rearwardly, compressing the spring 24, the carriage being thereafter shifted forwardly in accordance with the rotated position of the cam track 23.

Permanently mounted to the frame 12 is an adjustable stylus assembly 26 incorporating a laterally extending stylus or tracer member 27. The stylus assembly 26, as is conventional, incorporates adjustment means for axial and lateral adjustment, the net effect of which is to permit the tip 27' of the stylus 27 to be fixedly and accurately positioned in predetermined spaced relation to the cutting peripheral portion of the cutter wheel 18. The position of the stylus must be adjusted from time to time to compensate for wear of the cutter wheel.

It will be understood that the spacing of the stylus tip 27' and the cutting peripheral portion of the wheel 18 is arranged to correspond precisely with the spacing of a key and a key blank supported within the vises 10' and 10, respectively.

In the usual manner, when the carriage 13 is shifted forwardly and rearwardly by the box cam 22, the engagement of the stylus tip 27' against the pattern portion of a key supported in vise 10' will cause a sinuous pivotal or tilting movement of the carriage as the tracer scans the key, inducing a concomitant movement of the vise 10, which is equally spaced from the pivot radius of the rod 14. The eccentric weight orientation of the carriage would normally tend to induce a clockwise pivotal rotation of the carriage about the rod 14. A heavy spring member 28 links the carriage to the frame and overcomes this clockwise moment of the carriage, inducing a yieldable anticlockwise force, which force maintains the bits or pattern surface of the key in contact with the tip 27' of the stylus. In this essentially conventional manner, stylus-key contact causes a concomitant movement of the key blank against the cutter wheel, resulting in the milling or cutting away of the key blank to correspond with the bitting of the pattern key.

During the actual tracing and cutting, the key and the key blank must be immovably clamped within the vise assemblies 10' and 10. Clamping pressures are developed by vise actuator levers 29, 29', which actuates vises 10, 10', respectively. The vise actuator levers are pivoted at 30, 30', respectively, to portions of the carriage, the levers being urged in an anticlockwise direction about such pivots by springs 31, 31', respectively.

The levers include hardened vise actuator cams 32, 32' which bear against the upper surfaces 33, 33' of movable vise jaws 34, 34'. It will be appreciated that the springs 31, 31' thus normally tend to press the jaws 34 34' downwardly toward the clamping position of a key and key blank.

The levers 29, 29' are additionally provided with lift follower noses 35, 35', which follower noses bear against lift cams 36, 36' fixed to the frame. The lift cams include downwardly directed trailing follower release portions, the follower noses 35, 35' being engaged with the highest point of the cams 36, 36' when the machine is in its forwardmost position, as shown in FIG. 2. Due to the slope of the lift cams 36, 36', initial rearward movements of the carriage are accompanied by an anticlockwise movement of the levers 29, 29' under the influence of springs 31, 31', thereby allowing the force of the springs to press downwardly against the moving jaws 34, 34'.

It will thus be observed that when the carriage is in its forwardmost position, the jaws 34, 34' of the vises 10, 10' are free to move upwardly to their open position under the influence of lift springs 37--see FIG. 3, whereas upon initial rearward movement of the carriage, the portions 32, 32' will be permitted to bear against the jaws 34, 34', shifting the jaws from the open to the closed position.

It will be further understood that upon completion of a cutting cycle and return forward movement, the follower noses 35, 35' will again be lifted to their highest position, relieving the pressure on the upper surfaces 33, 33' of the vise jaws 34, 34', whereupon the jaws are opened under the influence of springs 37.

As thus far described, the cutting machine is entirely conventional, its operation being explained solely to permit a clearer understanding of the novel vise assembly most clearly shown in FIGS. 3 to 6. Since the vise assemblies 10, 10' are essentially identical, a description of the structure and operation of vise 10 will suffice.

The vise assembly 10 includes a fixed locking jaw 40 which is made fast to the carriage. The locking jaw includes an upstanding guide portion 41 having parallel outer walls 42, 43 which slide against the finer walls 44, 45 within the movable jaw 34 to permit the movable jaw an upward and downward movement relative to the fixed jaw 40. The fixed jaw is provided with a opposed pair of axially extending, outwardly open guide slots 46, 47.

A clamp head assembly 48 incorporates a pair of axially extending spaced legs 49, 50, the inner opposed portions of which legs are slidably received in and guided for axial movement on the slots 46, 47, respectively. An end bar 51 is mounted on the inner terminal ends of the legs 49, 50, the engagement of the bar 51 against the rear portion 52 of the fixed vise jaw 40 providing an outward limit stop for the clamp head assembly 48.

The clamp head assembly is provided with a recessed key receiver slot 53. A clearanceway 54 is formed downwardly through the upper face 55 of the end portion 56 of the clamp head assembly to provide clearance for actuation of the key-clamping components hereinafter to be described.

In the clamp head assembly, the under surface 57 forms a fixed clamp jaw, against which the under surface of the key will be disposed. The movable or upper clamp jaw 58 comprises an eccentric cam having a depending lobe 59. The cam is mounted on a pivot pin 60, the opposed ends of which pin are journaled in spaced coaxial bores 61, 62 formed in the clamp head 56 in alignment with the key receiver slot 52.

A bellcrank arm 63 is fixed to the pin and cam 58, the upper end 64 of the arm being provided with a pivot pin 65, which pin is pivotally connected to the inner end 66 of an actuator arm 67. It will be observed, with particular reference to FIG. 4, that a left-to-right movement of the actuator arm 67 will cause a clockwise movement of the pin 60 carrying the depending lobe 59 of clamp jaw 58 downwardly against the upper surface of the key, thus to wedge or bind the key tightly against the upper surface 57 of the clamp head assembly. Clearance for the movement of the bellcrank lever 63 is provided through the upwardly extending recess or clearanceway 54 in the clamp head assembly 48.

The clamp head 48 thus provides a initial clamping action against the head portion of the key. The final clamping action, i.e. the permanent clamping during the tracing and cutting of the key, is effected by the downward pressure of the vise jaw 34 against the lifting action of springs 37.

When the jaw 34 is depressed in the manner previously described, the horizontal under surface 68 of the jaw is brought to bear against an upper side part of the blade portion 69 of the key K. When the key is positioned within the slot 53, a portion of the under surface of the blade 69 is disposed atop the leg 49 of the clamp assembly, which leg is in coplanar alignment with surface 57 of the clamp head assembly.

As best seen in FIG. 6, the left-hand-most portion of the blade, i.e. the portion which will be cut or traced, projects laterally to the left beyond the vise assembly 10, to permit access thereto of the cutter wheel or stylus without interference with the vise. Thus, when the movable vise jaw 34 is depressed, the key blade will be tightly clamped between the under surface 68 of the jaw 34 and the upper surface 49' of the leg 49 of the clamp head assembly.

The upper jaw 34 has an axially directed clearance slot 70 to provide room for axial movement of the actuator arm 67. The rear end 71 of the actuator arm is guided for axial sliding movement relative to the drawbar 72, which drawbar is fixed to a solenoid assembly 73. Optionally, to provide the desired guiding function while permitting axial relative movement, the end 71 of the actuator arm 67 may have ears 74 embracing the drawbar.

Solenoid 73 includes a plunger 75, connected at 76 to the drawbar 72. A tension spring 77 is connected between aperture 78 on the actuator arm 67 and aperture 79 forming a part of the drawbar assembly. It will thus be observed that a rearward movement of the plunger 75 of the solenoid will carry the drawbar axially rearwardly with it, an the rearward movement will be likewise imparted to the actuator arm 67 through the medium of the tension spring 77. The coupling between the drawbar and the actuator arm may be properly described as a lost motion coupling since, when further rearward movement of the drawbar is prevented, e.g. by the lobe 59 being blocked against further movement by contact with a key K, the drawbar and, hence, the plunger is still permitted a further degree of rearward travel so that the plunger may proceed to its limiting position relative to the solenoid. By permitting the solenoid plunger to seat, chattering of the solenoid, as might be experienced if the plunger were prohibited from proceeding to a seated position, is prevented.

The mechanism for depthwisely positioning the key and for preventing relative tilting of the key and vise will next be described.

Depthwise location is effected responsive to a pair of switch and stop assemblies 80, 80' mounted on a shutter assembly 81 which is pivotally secured to the carriage. The switch and stop assemblies 80, 80' are identical in all respects, save that the means for seating (i.e. applying lateral force to) the pattern key in the vise 10' is independently pivotally mounted, whereas the force for holding the key blank in the vise 10 is a function of the pivotal force imparted to the entire shutter assembly. Accordingly, for purposes of clarification, the positioning assembly 80' will be described since much of the assembly 80 (as viewed in FIG. 3) is concealed by illustrated components of the vise 10.

The shutter 81 is pivotally mounted to the carriage by the pivotal connection of bearing aperture 82 on the headed trunnion 83 (see FIG. 2) made fast to the carriage. A tension spring 84 is connected between the shutter 81 and a portion of the carriage, to impart a clockwise biasing influence to the shutter. A portion 85 of the shutter 81 adjacent the vise assembly 10 presses against the key inserted into the vise assembly 10, the force of spring 84 thus biasing the base 86 of the key against outer wall 43 of the fixed jaw 40, serving as a reference point.

In the positioning assembly 80', the seating function performed by the part 85 is effected by a pivotal lever 85' mounted on pivot pin 86'. Spring means (not shown) bias the lever 85' in a clockwise direction, to permit the lever to serve the pattern key-seating function served in connection with vise 10 by the part 85. The use of independent holddown parts 85, 85' is required since the heightwise dimension of the key and key blank may vary, and the insertion of a key blank in the vise 10 would thus relieve tension and prevent the seating of a key in vise 10', should the height of the key blank exceed the height of the pattern key.

The shutter assembly 81 is pivoted in a counterclockwise direction clear of its screening relation of the vises in the course of the cutting and tracing action previously described. The pivoting of the shutter is caused by the interaction of a depending follower lobe 87 on the shutter against inclined cam 88 on the stationary frame 12 (see FIG. 2), it being understood that as the carriage moves rearwardly, the lobe 87 rides up the cam face 88 and the shutter is counterclockwisely pivoted against the action of the spring 84. When the carriage moves forwardly again, the lobe is cleared from the raised surfaces of the cam 88, permitting return movement of the shutter 81.

The positioning assembly 80' includes an upwardly extending arm 90, having a right angular recess 91 formed therein. A support leg 92, of lesser height than the arm 90, parallels the lower portion of the recess. A bellcrank switch actuator lever 93 is mounted in the recess 91 between the arm 90 and the leg 92. A pivot pin 94 extends through the junction between the upper leg 95 of the bellcrank lever arm and the lower leg 96 thereof.

As best seen in connection with the composite assembled vise 10 shown in FIG. 3, the upper leg 95 of the bellcrank lever 93 will be disposed in the path of the shoulder portion 97 of a key inserted into the slot 53 of the clamp head assembly. An actuating microswitch 98 is mounted to the front face of the shoulder 81 in such manner that its depressible switch contact 99 is disposed in alignment with the bellcrank lever 93.

The lower leg 96 of the lever includes a forwardly directed, inclined cam face 100. Spring means (not shown) project the upper leg 95 of the bellcrank lever forwardly, i.e. in the direction of insertion of the key, thus causing the cam surface 100 to be normally displaced rearwardly of the movable contact 99. It will be observed, however, that when a key is inserted through the slot so that its shoulder is pressed against the upper leg portion 95, said upper portion will be pivoted inwardly, inducing a forward movement of the leg 96, causing the cam 100 to depress the contact 99, closing the circuit through the microswitch 98.

In order to assure that the base 86 of the key is in precise axial alignment with a vise, each vise is equipped with a side alignment microswitch 101. The microswitch 101 is mounted on the fixed vise jaw 40 and includes a laterally directed, spring-projected contact plunger 102 which extends through a cross bore 103 in a fixed jaw into the path of the base 86 of the key. As best seen in FIG. 3, the base of a properly aligned key will depress the plunger 102, closing the circuit through microswitch 101.

Optionally but preferably, depthwise and sidewise alignment microswitches of each vise are connected in series so that the solenoids 73 controlling the respective vises cannot be actuated unless both switches are simultaneously depressed.

It is important to recognize that the microswitch 98 does not perform a depthwise alignment function. Rather, this switch, unlike prior art key-activated switching apparatuses, performs an energizing function, with final, accurate depthwise positioning being accomplished by automatic means in a manner hereinafter described.

A key is inserted in the vise through the slot 53 in such manner that its base 86 depresses the plunger 102, to close microswitch 101. Continued inward movement of the key will cause the key shoulder 97 to engage against upper leg portion 95 and a bellcrank lever 93 to induce a forward pivoting of the lower leg 96 of the bellcrank lever, causing the cam surface 100 to depress the trip contact 99 of microswitch 98. Assuming that microswitches 98 and 101 of each vise to be wired in series with a solenoid assembly 73 and a source of current, it will be observed that the solenoid will then be energized, causing inward movement of the plunger 75, which plunger is normally maintained in a forward position by spring 104 tensioned between the plunger and a fixed portion of the frame. Rearward movement of the plunger induces a rearward shifting movement of the drawbar 75 and, through the linking action of spring 77, the actuator arm 67. Rearward movement of the actuator arm causes a rotation of the pin 60 carrying clamping lobe 59, causing the clamping lobe 59 to press against the upper surface of the key.

The entire clamp head assembly 48 is free to slide forwardly and rearwardly relative to the fixed jaw 40 by reason of the previously described sliding engagement of the legs 49, 50 within the slots 46, 47. Spring means 105, compressed between a fixed portion of the frame and the bar 51, normally projects the clamp head to a forward position. This spring means is effective to maintain the clamp head in the noted forward position during the initial rearward movements of the actuator arm 67, i.e. until clamping pressures are developed between the lobe 59 connected to the actuator arm and the upper surface of the key. One such clamping pressures are developed, the contained rearward movement of the actuator arm 67 bodily carries with it the entire clamp head assembly 48. Inward axial movement of the clamp head assembly 48 results in a continued pivotal movement of the bellcrank lever 93 by reason of the engagement of the key shoulder against the leg 95 of the lever. In the course of this continued movement, the cam surface 100 may further depress the switch contact 99 beyond the amount required for initial energizing of microswitch 98. Thus, the clamp head assembly will continue to move rearwardly until the rear face of the upper leg 95 of the bellcrank lever bottoms against the forwardly directed face 106 of the channel or cutout 91 in arm 90. When the lever leg 95 is thus bottomed, further axial inward movement of the clamp head 48 will be positively prevented However, as previously noted, the solenoid plunger may continue its inward movement, due to the lost motion coupling connection between the drawbar 72 and the rear end 71 of the actuator arm 67.

It will thus be apparent that when a key or key blank is inserted into one of the vises 10 or 10', the key is sequentially gripped by the clamp head without any rearward movement of the clamp head and, after gripping is effected, the key is carried further inwardly to a bottom reference position relative to the vise.

By connecting the side alignment switch in series with the solenoid, it will be apparent that the clamp head assembly simply cannot be activated unless the base 86 of the key is in the exact, desired axial alignment.

Final depthwise referencing of the key and key blank is accomplished after initial tripping of the clamp mechanisms, thus to assure that the final setting movements of the key are accomplished by a precise axial inward movement of the key. Such precise axial inward movement is in contradistinction to key-cutting machines heretofore known wherein operation of a start switch is triggered by insertion of a key, the switch also being relied on to position the key. In all such known devices, there us a time interval between the tripping of the start switch by insertion of the key and the actual gripping of the key by the key machine mechanism. Without limitation, the failure of such key-cutting machines is considered, in large measure, to result from the possibility that the key may initially be inserted in a proper referenced position to trip a start switch, but during the time lag or interval between tripping of the switch and gripping of the key, the manual pressure employed to seat the key against the switch may induce a tilting or canting of the key.

The tendency toward unseating of the key from its aligned position in heretofore known devices is accentuated by the fact that the limit switch or other means utilized as the depthwise positioning means for the key, is powered by springs, which springs normally oppose the insertion of the key. Thus, should a user insert a key until the switch is activated by release the key immediately upon activation of the switch, the very act of releasing the key prematurely will subject the key to an unseating action by the limit switch. Accordingly, when the clamping mechanism finally permanently fixes the position of the key, the key will have been displaced a significant amount from its desired indexed position.

The problem in prior known machines is magnified by the fact that even a series connection employing such switch may not be relied on to deactivate the circuit of the machine since it is possible to insert a key beyond the distance necessary to trip a microswitch. In other words, even the protection of a series connected circuit is of no avail where the microswitch is tripped at a first position and continues to remain closed when the key is shifted beyond such position.

The device of the present invention overcomes the above-noted drawbacks by avoiding reliance on the microswitch as a depth-positioning means, and utilizing instead the switch to trigger means for clamping and thereafter moving the key until the shoulder is yieldably pressed firmly against a stop surface.

The final seating movement is effected by a precisely axially directed force. The lost motion coupling between the clamp head and the solenoid permits an overtravel in the manner previously set forth, thus permitting the unit to accommodate keys of a wide variety by varying dimensions.

Optionally but preferably, the circuitry which activates the key-cutting motor may be made responsive to the proper operation of the two vise members so that the key-cutting motor may not be energized through a cutting cycle until after the clamp heads of the two vises have engaged and advanced the key and key blank to the desired position.

From the foregoing it will be appreciated that in the device of the present invention the insertion of a key and blank results in an automatic positioning of the same in such manner that the key and blank are precisely disposed in a predetermined aligned position in the vises, whereby the pattern of a cut key is accurately reproduced on a key blank. The possibility of mispositioning either the key or the blank is eliminated. Since the concluding movements of seating the key and key blank against a desired reference shoulder or stop are effected, after initial clamping, by a precisely axially directed shifting mechanism, there is no possibility of misalignment of the key and blank, as is the case in other so-called automatic key-cutting machines heretofore known in which the key and/or the blank must be manually inserted into their ultimate positions.

It will be readily appreciated that the vises are not restricted in their application to key-cutting machines of any specific type but, rather, may advantageously be included in any automatic key-cutting machine.

The key-cutting device is particularly adapted for use in coin-operated vending machines due to the foolproof and fail safe nature of the loading procedure. Also, due to the automatic loading feature of the machine, the cutter may advantageously be employed in high volume key-cutting establishments wherein a single operator may be able simultaneously to operate several machines, due to the rapidity with which the machines may be loaded and the fact that the device requires no attention, once the key and blank have been inserted.

It will be understood that variations may be made of the concepts hereof without departing from the spirit of the invention and, accordingly, the invention is to be broadly construed within the scope of the appended claims.

Claims

Having thus described the invention and illustrated its use, what is claimed as new and is desired to be secured by Letters Patent is:

1. In an automatic key-cutting machine having a cutter, a stylus spaced from said cutter, support means for a key and key blank and means for relatively moving said support means and said cutter and stylus, first and second vise means on said support means, said vise means including an axially shiftable clamp head for supporting a key in a first position, said head having a fixed jaw member, a clamp jaw movably mounted relative to and shiftable toward and away from said fixed jaw member, spring means yieldably urging said clamp jaw away from said fixed jaw, and actuator means coupled with said clamp jaw for shifting said clamp jaw toward said fixed jaw against the yieldable pressure of said spring means and shifting said clamp head in said axial direction away from said first position upon development of clamping pressures of said movable jaw against a key on said fixed jaw.

2. A device in accordance with claim 1 and including a lost motion coupling between said actuator and clamp jaw.

3. A device in accordance with claim 1 and including first switch means positioned to be tripped by said key at said first position for energizing said actuator means, and stop means positioned to engage against a shoulder of said key and arrest axial movement of said key and clamp head when said key is shifted by said clamp head to a second position axially inwardly displaced from said first position.

4. A device in accordance with claim 3 and including second switch means positioned to engage the base of said key in said first inserted position, said second switch means and first switch means being connected in series with said actuator means whereby said actuator means can be energized only when said switches are simultaneously closed.

5. In an automatic key-cutting machine having a cutter, a stylus spaced from said cutter, support means for a key and key blank and means for relatively moving said support means and said cutter and stylus, first and second vise means on said support means spaced apart in accordance with the spacing of said cutter and stylus, said vise means including locking jaw means for holding said key and blank during tracing and cutting, a key positioning mechanism mounted on and shiftable axially relative to said locking jaw means for aligning said key and blank relative to said vise means, and actuator means for moving said positioning mechanism in said axial direction relative to said locking jaw means.

6. Apparatus in accordance with claim 5 wherein said positioning mechanism includes a fixed jaw, and a clamping jaw movable toward and away from said fixed jaw, and said actuator means is operatively associated with said clamping jaw, said positioning means being shifted in said axial direction responsive to predetermined pressure exerted by said clamping jaw against a key disposed between said fixed and clamping jaws.

7. A device in accordance with claim 6 and including spring means yieldably urging said clamping jaw away from said fixed jaw and said actuator means away from said axial direction, said spring means being effective to prevent axial shifting movement of said positioning means under the influence of said actuator means until predetermined pressures are exerted by said clamp jaw against said key.

8. A device in accordance with claim 7 wherein said spring means include first and second spring components, respectively urging said positioning means away from said axial direction and urging said clamp jaw away from said fixed jaw, the forces required to overcome said second spring component being less than the forces required to overcome said first spring component.

9. In an automatic key-cutting machine having a cutter, a stylus spaced from said cutter, support means for a key and key blank and means for relatively moving said support means and said cutter and stylus, first and second vise means for positioning and clamping said key and blank during cutting and tracing, said vise means including a clamp head having a fixed jaw, a bellcrank lever pivotally mounted on said clamp head and including a clamp jaw arm and a actuator arm, first spring means yieldably urging said lever to a key-receiving pivoted position in which said clamp jaw arm is spaced from said fixed jaw, actuator means operatively connected to said actuator arm for urging said arm in said axial direction, thereby to pivot said clamp jaw arm toward said fixed jaw and thereafter to shift said clamp head in said axial direction upon development of clamping pressures of said jaw arm against a key disposed between said fixed jaw and jaw arm.

10. A device in accordance with claim 9 and including second spring means yieldingly urging said head away from said axial direction, the forces required to shift said head in said axial direction against said second spring means exceeding the forces required to pivot said clamp arm against the influence of said first spring means.

11. A key-cutting apparatus including cutter and tracer means, support means movable relative to said cutter and tracer means and vises for holding a key and key blank on said support means, each said vise including a locking jaw, clamp head means movably mounted relative to said locking jaw for gripping a key and shifting said key axially relative to said locking jaw, switch means operated responsive to insertion of a key into said clamp head to a first position for fixing said key to said clamp head against relative movement and actuator means operated responsive to the fixing of said key to said clamp head for shifting said clamp head to a predetermined indexed position relative to said locking jaw, thus to advance said key to a second, predetermined position.

12. A device in accordance with claim 11 and including means for clampingly engaging said locking jaw against said key responsive to relative movement of said support means and cutter and tracer means.

13. A device in accordance with claim 11 and including holddown means positioned to engage said key and blank for seating the bases of said key and blank in said vises, means for clearing said holddown means from engagement with said key and blank during the tracing and cutting of said blank and said key, said switch means being mounted on said holddown means.

14. The combination of claim 11 and including stop means on said support means positioned in the path of movement of a key held in said clamp head to engage and locate said key in said indexed position.

15. The combination of claim 14 and including a lost motion coupling connected between said actuator means and said clamp head.

16. The combination of claim 15 wherein said lost motion connection includes a tension spring whereby said key is yieldingly held against said stop means.